Convertible sawing and abrading machine



Nov. 14, 1939. L A., wlLKlE 2,180,079

CONVERTIBLE SAWING AND ABRADING `MACHINE Filed Jan. 7, 195s 5sheets-sheet 1 Nov. 14, 1939. L.. A. wlLKlE CONVERTIBLE SAWING ANDABRADING MACHINE 5 Sheets-sheet 2 Filed Jan. 7, 1938 Nov. 14, 1939. L, AWILKIE 2,180,079

CONVERTIBLE SAWING AND ABRADING MACHINE Filed Jan. 7, 1938 5Sheets-Sheet 3 Nov. 14, 1939.

CONVERTIBLE SAWING'-AND ABRADING MACHINE Filed Jan. 7, 1938 5SheetsLSheet 4 Nov. I4, 1939. 1 A. wlLKlr-z -2,180,079

CONVERTIBLE SAWING AND ABRADING MACHINE Filed Jan. 7, 1958 i 5Sheets-Sheet 5 ,lf2/Menton' Patented Nov. 14, 1939 UNITED STATES vPATENT'oFFicE Leighton A. Wilkie, Minneapolis, Minn., assignor to ContinentalMachines,

Incorporated, Minneapolis, Minn., a corporation of Minnesota.

Application January 7, In C anada February 27 Claims.

This invention relates to a convertible machine for abrading, polishing,sawing, and the like; and constitutes a continuation in part of thecopending application of Leighton A. Wilkie, iiled May 27, 1935, SerialNo. 23,554.

The invention has for one of its objects, the provision of a new andimproved machine that may be readily converted into a band saw, a iilingor abrading device`, or a polishing machine, as occasion may require.

Another object of the invention is the provision of a new and improvedconvertible sawing and abrading device together with novel means forwelding the ends of the band when the same is severed or becomes broken.

A further object of the invention is the provision of new and improvedmeans for facilitating the removal and replacement of bands forperforming various different operations by the same band operatingmechanism.

A further object of the invention is the provision of a new and improvedconvertible abrading, polishing and sawing mechanism that is simple inconstruction, eicient in operation, composed of few moving parts, easilyassembled, that is compact and comparatively light in weight, and thatmay be readilychanged from one type of operating mechanism into another.

Other and furtherxobjectsl 'and advantages of the invention will appearfrom the following description taken inA connection with theaccompanying drawings, in which Fig. 1 is a side elevation ofthe machineshowing the same as being used as a band saw device;

Fig. 2 is a front elevation thereof, with parts broken away;

Fig. 3 is a side elevation of the machine showing the same convertedinto an abrading or fLling ,machine;

Fig. 4 is a front elevation of a portion of the band and abrading devicetogether with its guides and a portion of the table;

Fig. 5 is a section on the line 5-5 of Fig. 4;

Fig. 6 is a section on the line 6--6 of Fig. 4;

Fig. 7 is a perspective view of the guide or backing member and aportion of the band;

Fig. 8 is a perspective view of two adjacent le elements;

Fig. 9 is a vertical sectionon the line 9-9 of Fig. 4;

Fig. 10 is a Vertical with parts broken away, grinding mechanism;

Fig. 11 is a diagrammatic View showing the welding mechanism;

section of the machine, showing the welding and 1938, Serial No. 183,764

Fig. 12 is a section on the line l2-l2 of Fig. 10;

Fig. 13 is a top plan view of the holding members for the weldingmechanism, with parts broken away; and

Fig. 14 is a side elevation of a portion of the 5 machine, with partsbroken away; but showing the holding mechanism and control lever for thewelding device on an enlarged scale.

The equipment for modern machine shops requires various types ofmechanism for performing numerous kinds of operations required from timeto time in the normal functioning of the shop, such, for instance, assawing, abrading, polishing and the like. It is common practice toprovide separate machines for the diierent oper- .15 ations but such anarrangement is objectionable for numerous reasons." y

Additional ooi" space` must be provided and where the. workspaceis'limited, this is a serious problem. Furthermore, the expense ofproviding 2o a separate machine for performing eachoperation is a veryserious consideration, especially with the"` more modest shop owner.Then, too, with too" many machines, those while not in use will be moreor less in the-way of the. operator in using g5 the other machines.

The present invention seeks to overcome these diiculties by theprovision of a single mechanism f' occupying a minimum o f space thatmay be readily and easily changed from a machine ior'pera0 forming onetype of work to another with a mini.- mum of time and expense. In orderthat this may be done expeditiously, the device is made complete withall the necessary mechanism for effecting the change. 'I'his mechanismincludes Il a welding device and grinder whereby in the change fromfiling to sawing where the saw is inserted through a closed opening, forinstance, the change may be readily made. In making the change, the sawis severed, then inserted through im the opening in the work and theends welded, the welded part tempered and the weld ground, after whichthe band is trained around the pulleys. The entire time consumed inmaking the change will not be more than from one to three minutes. 4t

Referring now to the drawings, the reference character 5 designatesgenerally the combined sawing, abrading and filing machine whichcomprises a base 6, Figs. 1, 2 and 3, on which is mounted the motor andoperating mechanism 5 for the device and on which is mounted anoverhanging arm portion 1. The base 6 and arm portion 1 are housedwithin a casing 8 which conforms roughly to the form of the device. Thelower portion of the casing is provided with a sa of adjacent side door9 and the upper portion with the doors I3 and II. The intermediateportion of the casing is provided with an opening covered by a closureor closure plate I2 on which the welding mechanism is mounted as willpresently appear. The base and overhanging arm support the verticallyalined pulleys |3 and' I4 as is usual in such constructions.

As shown, a band saw blade I5 is trained about the pulleys I3 and I4 inthe usual manner, Figs. 1 and 2. A conventional saw band guide I6,adjustable through the bracket 44, is provided, and the base has theconventional table I1 mounted on the same through which the saw bandextends. The bracket 44 is shown in Fig. 3 and is rigidly mounted in theframe of the machine. The pulleys I3 and I4 are operated by a suitablemotor I3 mounted on the base 6 within the casing 8 as shown in dottedlines in Fig. 1.` This motor is geared to a change speed mechanism I 9by a belt or chain 2| and this in turn is geared to a drive pulley 22 bya suitable belt or drive chain 23. The change speed device is manuallyadjusted by a suitable hand wheel 23 as will presently appear. A pinion24, keyed to the shaft of the pulley 22, meshes with a gear 25 on theshaft on which the pulley I3 is mounted. It will thus be seen that bymeans of this arrangement, the pulley I3 is geared down and that itsspeed is considerably reduced from4 that of the motor shaft. The journal26 for the shaft of the pulley I4 is adjustably mounted in the slot 21in a portion of the arm 1 of the apparatus in the usual manner. Sincethis is'conventional, it is not thought necessary to further illustrateor describe the same. It is by means of this adjustment that tension maybe placed on the band for operating the same and the tension releasedwhereby the band may be attached and detached as will presently appear.

When it is desired to employ the device as a ling machine as shown inFigs. 3 to 9, inclusive, the saw band I5 is removed from the pulleys andthe guide I6 is also removed from the supporting bracket 44 and a illeband and a backing member are applied as will presently appear.

The filing mechanism, comprises an endless flexible metallic band 23 towhich a plurality of file elements 29 are attached. The adjacent ends.of the flle elements 29 interengage. Each ille element 29 has a reducedportion 3| extending forwardly therefrom and this reduced portion formsa shoulder 32 extending transversely across the outer surface of thefile element The extension 3| is curved on its outer surface, as shownmore clearly in Fig. 7 of the drawings. The contiguous end of theadjacent file element is provided with a corresponding recess 333 forreceiving the extension 3|. By providing the outer surface of the pro-Jection 3| with a curved surface for engaging a corresponding recess 330in the continuous end of the adjacent ille element, the ends of theilling elements are guided into alinement. In other words, the convexsurface of each projection, which may be considered as a surfaceconverging outwardly, engaging the recess having what may be consideredas surfaces .diverging inwardly, cooperates with said recess to guidethe contacting ends of the file elements into perfect alinement. Therecess 333 and projection 3| ille sections interilt in such a manner asto prevent relative lateral movement of e ends of the ille elementsrelative to each l other and during the passage of the ille band Figs. 3to 9, inclusive,`

across the working zone. The shoulder 32 of the following file elementabuts the adjacent end of the preceding ille element thereby formingsubstantially continuous filing surfaces.

The ille elements are secured to the band by any suitable means such asthe rivets or screws 33 which engage an end portion of the ille elementsand rigidly connect the same to the bands. The le elements are connectedto the band adjacent to the advancing ends thereof in order that the endhaving the projection 3| will be held adjacent the band while movingaround the pulleys whereby the reduced portion will be in position to beproperly engaged by the free end of the following ille on the straightrun of the band.

Since the ille elements are attached to a metal band, there is nostretching of the band and consequently, the surface of the illingelement will remain smooth and continuous.

Suitable means are provided for resisting the yielding movement of theille elements when the work is forced against the same during theoperation of the machine. In the form of the construction shown, abacking member 33 is employed for this purpose. This backing membercomprises a channel element 34 having rabbets 35 in the inner side ofeach ilange 36 forming ledges 43 on which the ille elements or the fileband, if it be made as wide as the flle elements,

may travel. The depth of these rabbets is such that the flanges '36 willextend alongside the illing elements '29 at each side edge thereof forguiding the same in their movement. The depth of the groove beyond theledges 43 is such that suillcient clearance for the band 23 is provided.

The intermediate portion of the channel member 34 of the portionopposite the table I1 has its sides removed as at 31 on each sidethereof so that the width of the backing member 33 will lnot be greaterimmediately above the table than that of the ille elements whereby theuse of the endless ille in corners and the like will be permitted. Inorder to facilitate the attachment and removal of the band 28, the sameis split and has one end provided with a keyhole slot 33 that is adaptedto vengage a headed pin 33 on one of the ille. elements. In connectingthe ends of the band, the end portions are disposed at right angles toeach other and engaged ilatwise with the pin entering the large end ofthe keyhole. After sliding the pin into the narrow end of the keyhole,the two end portions are swung into alignment with the ends of the bandabutting, this being permitted by the rounded ends of the band.

In the operation of the device, the ille elements will ride on theshoulders or ledges 43 formed by the rabbets 35 as shownin Fig. 6, andthe band 23 will be disposed in the slot below the rabbets, the slotbeing of such depth as to provide sufflcient clearance for theoverlapping ends of the band. When in operation, the flles movedownwardly along the backing member 34 and the inner edges of theflanges 33 are bevelled outwardly as at 4| to assist in guiding,l theends of the ille elements into the channel at the lower end of thenarrow portion 31 of the backing member.

Suitable means are provided for raising and lowering the backing member34. bracket 42 attached to the backing member has an upwardly extendingarm 43, Fig. 3, which is adjustably mounted in the bracket 44 on theframe of the machine.

As shown. a`

Appropriate means are also provided for holding the band iand fileelements in position in the backing member 34. As shown, a plurality ofrollers mounted in a U-shaped bracket 46 for engaging the forward sideof the file elements are provided for this purpose. The bracket 4B hasone arm extended and provided with a horizontal slot 41 in which isadapted to engage an adjusting bolt 48, Fig. 5. The bolt also extendsthrough a vertical slot 49 in a bracket 50 rigidly secured to the backof the backing member 34 which will permit not only an inner and outermovement of the bracket 46 and rollers 45, relative to the backingmember 30, but will permit the same to be adjusted vertically.

In sawing and abrading metal, the speed of the band must be varied forvarious kinds of metals and for the different tools employed. It hasbeen found that the speed of the bands for filing or sawing soft metalsis many times greater than when operating on hard material. Forinstance, while the velocity of the band in operating on chrome steel ofa given thickness should be approximately 'l5 feet per minute, the speedof the band may be increased to as much as 400 feet per minute whenoperating on softer metal of the same thickness. Likewise, the speeds ofthe band will depend on the kind and thickness of the metal and thelike.

Furthermore, the speed at which the saw band or abrading band operatesmost advantageously is within comparatively narrow limits. Experiencehas shown, for instance, that the convential stepped pulley for securingthe different speeds does not give that variation in speeds required tooperate most efliciently under the various operating conditions to whichdevices of this nature are subjected.

`In Figs. l, 2 and 3 is disclosed a device with which any variation ofspeed of the abrading or sawing band within limits, may be obtained. Inthe form of construction shown, which is by way of example only, thechange speed device I9 comprises a. shaft I on which are keyed a pair ofexpansive pulleys 2 and 3. Each pulley comprises a pair of complementarysections 4 and 5a slidable along the shaft I. Each section iscone-shaped on its inner side and each cone comprises a series ofprojections 6a alternating with recesses 'la and the projections andrecesses of one section are adapted to engage the recesses andprojections, respectively, of the other section, somewhat like the teethof a gear. Springs 8a and 8b at opposite sides of each pulley normallyforce the sections together to form V-shaped grooves in which theconventional V- shaped belts 2| and 23 are adapted to engage. Suitablemeans are provided for simultaneously tightening the belt 2| andloosening the belt 23 and vice versa for obtaining a fine adjustment orchange of speed of the saw or abrading belt.

In the construction shown, brackets 9a, through which a threaded rod 9bextends, constitute the journal of the shaft I. `-The rod 9b isjournaled in suitable brackets secured to the casing 8 and is rotatedbyy a hand wheel 20 through bevel gears 9c,Fig. 1. When the handle 20 isoperated in one direction, the bracket 9a will travel upward carryingwith it the pulleys 2 and 3. As the pulleys move upward, the tension onthe band 23 is released whereby the springs 8a and 8b will force the twosections of the pulley 2 toward each other thereby increasing theeffective diameter of the pulley 2. The movement of the shaft I willplace more tension on the V-belt 2| and this in turn will crowd thesections of the pulley 3 outward against the tension of the springs 8aand 3b whereby the eective diameter of the pulley 3 will be decreased.As a result of these changes in these two pulleys, the speed of the sawor abrading band will gradually increase. The opposite effect isobtained by turning the handle 20 in the opposite direction. With suchan arrangement, the finest adjustment in speed may be obtained. v

In the use of integral endless bands, as for instance in sawing, it isdesirable that means be provided for connecting thel ends of the bandwhen the same become broken or when it is desirable to sever the band inorder to insert the same in a closed opening for operating therein. Theapparatus is provided with means for accomplishing this result therebyreducing ,the

time necessary to repair the band to a minimum.

In connecting the ends of steel bands, it has been proposed to brazethe` same but this requires the ends of the band to be scarfed andoverlapped thereby consuming time and labor and a material shortening ofthe band. The present invention contemplates the use of a welding devicefor butt welding the ends of the band. Means are also provided forVremoving the flash or reducing the welded part to the desired thicknessafter the welding operation.

' In the form of the device selected to illustrate one embodiment of theinvention, a welding mechanism 52,"housed in the rear portion of thecasing 8 and mounted on the removable plate I2 is provided. Thismechanism has a fixed terminal 53 and a movable terminal 54, Fig. 11,extending to the exterior of the casing as shown in Fig. l. Theseterminals are each provided with clamping members for clamping the endsof the band fixedly to the terminals 53 and 54. These clamping membersmay be of any suitable form, but as shown on the drawing, the terminals53 and 54 are provided at their outer ends with slots' 56, Fig. l1, inwhich is movably mounted a clamping block 51 whichis adapted to beforced downwardly against the ends of the band for clamping the sameagainst the lower marginal surface of the slot. Suitable screws 58,swiveled at their lower ends in the blocks 51, are provided for thispurpose. The terminals have inwardly extending projections 53a and 54a,Fig. 13, adjacent the inner ends of the slots for shortening the gapbetween the terminals at that point whereas the outer ends of theterminals are much farther apart. The former is desirable for weldingand the latter for annealing, as will presently appear.

The movable terminal 54 is rigidly connected to a swinging arm 59, Fig.11, which is pivoted as at 6| to the plate I2, Fig. 10. A spring 64normaly holds the movable terminal 54 out of contact with the stationaryterminal 53. While in use, the movable terminal is held inwardly by acontrol lever 62. The lever 62 is rigidly connected to a shaft 63extending through and pivoted in the closure plate l2. An arm 1|),rigidly secured to the shaft 63 and connected to the inner end of thespring 64, is adapted to be moved forwardly by the handle 62 for movingthe arm 59 forwardly, and with it, the terminal 54, as will presentlyappear. The arm 'I0 is preferably provided with an adjustable Contactscrew which engages the arm 59 as clearly shown in Fig. 12 of thedrawings. This screw is adapted to be adjusted to the desired length forcausing the proper movement of the arm 59 when engaged by the screw 60upon the release of the lever 62. The arm 10 is held rearwardly by thespring 64 which, in the construction shown, extends through an enlargedopening 65 in the terminal supporting arm 59. A pin 65a extendingtransversely through the spring 64 serves to connect each end portion tothe arm 59. The lever 62 is located outwardly of the plate I2, Figs. 1,11 and 12, constitutes a means for moving the terminal 54 for causing itto swing inward to bring the ends of the band into contact as willpresently appear.

It is desirable that the parts be so arranged that when the lever`62 isdepressed, it will operate a switch for closing the welding circuitthrough the abutting ends of the band. Means are also provided forautomatically opening a switch in the welding circuit when the weldingoperation is complete. In the form of the construction shown, Figs. 11and 12, the switch 61 is closed by the arm 10 which will force themovable elements 68 of the switch against the iixed contacts 69 when thelever 62 is pressed downward. In practice, the arm 10 is adapted toengage a spring pressed button 1I, Fig. 12, for closing the switch whenit is depressed and to open the switch when it is released.

'I'he switch 61 is adjustably secured in position on the wall closureplate I2 by any suitable means. As shown, a bracket 12, Fig. 12, havingan outstanding flange 13 is secured to the wall oi' the closure plateI2. The flange 13 is provided with an opening through which a threadedstem 14, secured to the switch 61, extends. This stem is adjustablymounted by means of the nuts 15 on the stem 14 at each side of theflange 13. By means of these nuts, the position of the button 1I may bebrought nearer or farther from the arm 10.

Any suitable mechanism is providedfor automatically opening a switch inthe primary of the welding circuit when the welding operation iscompleted. In the form of the device shown in Figs. 11 and 12, a mercuryswitch 16 is employed for this purpose. The switch16'has an upstandingarm 11 pivoted as at-18 to the closure plate I2 and has a lowerextending arm 19 provided with a slot 8| which is adapted to be engagedby a pin 82 on the upper end of a swinging arm 83, pivoted at its lowerend as at 84. The arm 83 has an extension 85 which is slotted as at 86for engaging the pin 81 on an armv 88 carried by the movable terminal.'I'he parts are so proportioned that when the movable terminal 54 ismoved inward by the lever 62, the inward swinging of the arm 59 willcause the arm 83 to move about' the pivot 84 and this in turn will tiltthe mercury bulb switch 16 and open the circuit which is normally closedwhen the device is not in operation.

A suitable transformer 89, Figs. 10 and 11, having a. primary winding 9|having the switches 61 and 16 therein and a secondary winding 92connected with the terminals 53 and 54 are employed for furnishing thecurrent for performing the welding operation. Since the details of thetransformer and the wiring arrangement constitute no part of the presentinvention, it is not thought necessary to illustrate and describe thesame more in detail other than to f state that the lead 93 of thesecondary winding 92 that is connected with the movable terminal 54 ispreferably flat as shown in Fig. 10 so as to provide suicientflexibility to permit the proper movement of the terminal block 54.

In the operation of the device, the two ends of the band to be weldedare inserted in the inner ends of the slots beneath the projections 63aand 54a and are clamped in position in end to end alinement, the lever62 is depressed for forcing the lever 59 inward for closing the switch69 and held in lowered position whereby the tension of the spring 64will cause the ends of the band to be yieldingly forced against eachother. As the abutting ends oi' the saw are softened, the pressure willcause them to shorten due to the swedging of the heated ends. Thetension of the spring 64 will cause said block to move farther andfarther inward until it tilts the mercury switch 16 sufcient vto openthe circuit. The lever 62 is then released and the set screws 58unscrewed, which will permit the arm 59 to be retracted by the spring64. 'Ihe band is now welded but is very hard. In order to temper theweld, the band is slid forward to the outer endsof the slots as shown indotted lines in Fig. 13 and again clamped in position after which thelever 62 is depressed for an instant until the weld becomes blue incolor and is then released. This reheating for an instant to a bluecolor anneals the Welded portion.

After the welding operation, it is necessary to remove the ilash orenlargements at the weld. 'I'he welding operation causes a thickening ofthe band and this thickened portion must be reduced before the band canbe used. Suitable means are provided for grinding the band to the properdimensions. As shown, a grinder 94 is mounted on the ledge 95 'andoperates about a horizontal axis. 'Ihe grinder may be mounted on thearmature shaft of the motor 96 which operatesl thegrinder. "A shield 91.is preferablym provided for theV grinder 94.

It will thusl be'seen that a combination.` device is provided which maybe readily and easily' changed so as to'perform various operations at aminimum of time, labor and expense.

While the deviceis described as being convertible into a band'saw oriiling machine, it is understood that it may be used asa polishingdevice or sanding machine depending on the nature of the band andelements used therewith.

It is thought from the foregoing taken in connection with theaccompanying drawings that the construction and operation of my devicewill be apparent to those skilled in the art, and that changes in size,shape, proportion and details of construction may be made withoutdeparting from the spirit andscope of the appended claims.

I claim as my invention: l

1. In an abrading device, a pair of pulleys, a metallic one piece bandtrained about said pulleys, means for rotating one of said pulleys, fileelements rigidly connected to said band, the adjacent ends of said fileelements interftting and having their ends abutting continuously acrosssaid elements along a line at right angles to the edges of said band.and means on the adjacent ends of said band for detachably connectingthe same together whereby said band may be inserted in closed openingsfor filing the interior thereof and for removing the band and elementsfrom along a straight line at right angles to said band continuouslyacross said elements.

3. In an abrading device, a flexible band, abrading elements, means forsecuring the intermediate portions of said elements to said band, andoverlapping intertting connections between the adjacent ends oi saidelements, the joint be` tween the abrading surfaces being straight andat right angles to the center line of the'band and extending entirelyvacross said elements.

4. In a convertible metal ling and sawing machine, a frame, a pair ofpulleys mounted in vertically spaced relation on said frame, a worktable rigidly mounted onsaid frame between said pulleys and having anopening therethrough, a thin metal band trained about said pulleys andextending through said opening, a backing member having means at itsends only for preventing the lateral movement of said band, said thinmetal band having flle elements thereon movable along said guides, theedgewise stiffness of said band preventing lateral movement of said bandand filing elements between the ends of said backing member, means fordetachably mounting said backingl member on said frame whereby saidbacking member and band may be removed, and a saw band mounted on saidpulleys.`

5. An abrading device comprising an endless iiexible steel band, meansfor supporting and moving said band, abrading elements secured to saidband, a band guide comprising a channel member having a rabbet in theinner surface of each flange for guiding said band and elements` andhaving portions of said iianges removed from the exterior of saidflanges adjacent to the points where the Work is applied to the abradingelements whereby said band will be guided in its movement from the endsof the guide and said elements will be exposed for abrading said work atthe point where said portions of the anges are removed.

6. In an abrading device, a channel member having ledges on the innersurfaces of the ilanges for receiving a band of iile elements and havingthe sides of the flanges between the endsof the channel member removedtoa depth equal to the thickness of the flanges outwardly oi' said ledgesto form a reduced portion in said member no wider than said flleelements.

7. In a device of the class described, a base, a pair of verticallyspaced pulleys mounted on said base, a metallic exible band trainedabout said pulleys, and abrading elements mounted on said band, saidelements having overlapping interengig connections between the adjacentends of adjacent elements so formed that the joints between the meetingends of the abrading elements on the abrading surface are substantiallynormal to the center line of the band.

8. In combination, a base, a support on the base, a pair of pulleysspaced'vertically and edgewise on said support, a work rest on saidsupport between the pulleys, a steel band trained about said pulleys,abrading elements secured to the outer side of said band, a guide devicefor said band extending above and below said work rest, the upper andlower ends of said guide device being in the form of channels havingside flanges between which the connected band and abrading elementsslide so that the guide device supports the connected band and abradingelements against the inward iiatwise pressure of work against theabrading elements and against edgewise displacement, the portion of theguide device between its channeled ends being no wider than said bandextends, a backing member for said band in said working zone, saidmember extending above and below said table4 and having its endsprovided with flanges extending outwardly alongside the side edges ofsaid file elements for guiding the same, the portion of 'said Vguide insaid working zone being no wider than said elements, a support for saidmember, means for removably mounting said support on said frame, saidband being severed and having means for detachably connecting thesevered ends together whereby said backing member and band may beremoved, and another band mounted in its stead.

10. In a device of the class described, a frame, a pair of pulleyssupported on said frame in spaced relation in a vertical plane, asubstantially horizontal table supported by said frame between saidpulleys and providing a Working zone above the same, a one-pieceiiexiblev metallic band trained over said pulleys and extending throughan opening in said table, le elements each secured to said band atpoints between its ends and having a ling surface on the side oppositesaid band, the adjacent ends of said elements being provided withsemi-circular projections and cooperating recesses interlockingtherewith and located inwardly of the filing surface, the outer sides ofsaid elements abutting in the working zone to form a continuous filingsurface, and a backing member on the inner side of said band forresisting inward pressure applied to the work during the operation ofthe device.

11. In an abrading device, a flexible band, le elements having abradingsurfaces, means for securing the intermediate portions of said elementsto said band, `the outer surfaces of adjacent elements abutting to forma continuous filing surface while in use, and overlapping interttingconnections between the adjacent ends of said elements, saidinterfltting connections being 'ing above and blow the table forsupporting the connected band and file elements against the pressure ofwork applied to the ille elements, side guides at the ends only of saidbacking member for supporting the connected band and le elements againstedgewise displacement above and below the working zone "but not in it,the intermediate portion of said backing member being no wider than saidille elements', and the stinness of the band against edgewise ilexuresupporting the connected band and file elements against edgewisedisplacement in the working zone between said side guides.

13. In an abrading machine, the combination of, a work supporting tablehaving a hole therethrough, the space'directly above the'tableconstituting a working zone, a pulley above the table, a pulley beneaththe table, a one-piece ribbonlike metal band trained over said pulleysand passing through the hole in the work supporting table. abradingelements attached medially of their ends to said flexible band to besuccessively carried thereby through the working zone, rigid guide meanssupporting said band and abrading elements adjacent to the working zonebut not in the working zone against edgewise displacement out o f theirintended path, and a rigid backup support for the connected band andabrading elements, said rigid backup support extending substantiallyacross the working zone and being sumciently narrower than said rigidguide means to have no portion thereof extend beyond the side edges ofthe abrading elements whereby the abrading elements may enter corners ofwork without interference from the backup support, said connected bandand abrading elements being supported against edgewise displacement incrossing the working zone solely by the stiness oi' the band againstedgewise flexure.

14. In an. abrading machine, the. combination of, -edgewise spacedpulleys, a one-piece metal band trained about said pulleys and movingwith a straight run through a distance between said pulleys, said bandbeing atwise flexible to enable it to follow the curvature of thepulleys, but being wide enough to be edgewise inflexible, a plurality ofabrading elements carried by said band to be successively movablethereby through said space,

means for supporting work in juxtaposition to the abrading elements asthey move through said space so that said space constitutes a workingzone, guide means adjacent to but entirely outside the working zone forsupporting the band against edgewise displacement during its travelthrough the Working zone, and a backup support for supporting the bandand the abrading elements carried thereby against iiatwise displacelment by the pressure of work applied to the abrading elements, saidbackup support extending across the working zone' and being sufcientlynarrow than said rigid guide means to have no portion thereof extendbeyond the side edges of the abrading elements whereby the abradingelements may enter corners of work without interference from the backupsupport. A

15. In an abrading machine, the combination of, edgewise spaced pulleys,a one-piece metal band trained about said pulleys and moving with astraight run through a distance between said pulleys, said band beingflatwise exible to enable s. itjto follow the curvature of the pulleysbut being y wide enough to be edgewise iniiexible, a plurality againstedgewise displacement during its travel through the working zone, and arigid supporting member having a longitudinally continuous surface alongwhich the band and abrading elements travel, said supporting memberbeing disposed in the working zone to support the abrading elementsagainst the pressure applied thereon by the work, and being suilicientlynarrower than said rigid guide means vto have no portion thereof extendbeyond the side edges of the abrading elements whereby the abradingelements may enter corners of work without interference from thesupporting member.

16. In an abrading machine, the combination of, edgewise spaced pulleys,a' flat ribbon-like onepiece metal band encircling the pulleys, saidband being wide enough to be edgewise inflexible so that a portion ofthe band spanning the distance between two supports which hold the sameagainstedgewise displacement is held by the inherent stiffness of theband itself against edgewise motion, .a plurality of abrading elementscarried by the band, means for supporting work to be lacted upon by theabrading elements, said means being located in juxtaposition to onestretch of the band as it passes from pulley to pulley so that the spaceadjacent to the work supporting means constitutes a working zone, meansabove and beneath but not in the working zone for supporting the bandagainst edgewise displacement, and a continuous backup support extendingthrough the working zone between said supporting means to support theband and abrading elements against iiatwise displacement in the workingzone, said backup support being no wider than the abrading elements soas not to interfere with proper functioning of the abrading elements incorners of work.

17. In an abrading machine, the combination of, edgewise spaced pulleys,a flat ribbon-like onepiece metal band encircling the pulleys, said bandinherent stiness of the band itself against edgewise motion, a pluralityof abrading elements carried by the band, means for supporting work tobe acted upon by the abrading elements, said means being located injuxtaposition to one stretch of the band as it passes from pulley topulley so that the space adjacent to the work supporting meansconstitutes a working zone, means above but not in the working zone forsupporting the band and the abrading elements thereon against edgewisedisplacement,I and a backup support extending Vsubstantially through theworking zone and having a longitudinally continuous surface along withthe band and abrading elements slide to be supported against iiatwisedisplacement, and said backup support being no wider than the abradingelements so as not to interfere with proper functioning of the abradingelements in corners of Work.

18. In an abrading machine, the combination of,.edgewise spaced pulleys,a fiat ribbon-like onepiece metal band encircling the pulleys, said bandbeing wide enough to be edgewise inflexible, a plurality of abradingelements carried by the band, means for supporting work to be acted uponby the abrading elements, said means being located in juxtaposition toone stretch of the band as it passes from pulley to pulley so that thespace adjacent to the work supporting means constitutes a working zone,a. backup support having a longitudinally continuous surface along whichthe band and abrading elements slide, means rigidly mounting saidbackupsupport with the ends thereof extending above and beneath the edgesthereof to engage over the sides of the connected bandand abradingelements and thereby support the band and abrading elements outside theworking zone against edgewise displacement, said means engaging theconnected band and abrading elements for an extent long enough to insurethat the inherent stiffness of the band against edgewise ilexure holdsthe same and the abrading elements against edgewise displacement in theworking zone. f

19. In an abrading machine, the combination of, edgewise spaced pulleys,a iiat ribbon-like onepiece metal band encircling the pulleys, said bandbeing wide enough to be edgewise inexible, a plurality of abradingelements carried by the band, means for supporting work to be acted uponby Lthe abrading elements, said means being located in juxtaposition toone stretch of the band as it passes from pulley to pulley so thatr thespace adjacent to the work supporting means constitutes a working zone,a backup support having a longitudinally continuous surface along which.the band and abrading elements slide, means rigidly mounting said backupsupport with the ends thereof extending above and beneath the workingzone, said backup support being no wider than the abrading elements, andmeans directly connected with said backup support at the opposite endsthereof to be disposed above and beneath the working zone and projectingbeyond the side edges of the backup support to engage over the sides ofthe connected band and abrading elements and thereby support the bandand abrading elements outside the working zone against edgewisedisplacement, said last named means providing two supports close enoughtogether that the portion of the connected band and abrading elementsspanning the distance therebetween is held against edgewise displacementby the inherent stiffness of the band itself.

20. In an abrading machine, the combination of, edgewise spaced pulleys,a iiat ribbon-like onepiece metal band encircling the pulleys, said bandbeing wide enough to be edgewise inflexible so that a portion of theband spanning the distance between two supports which hold the sameagainst edgewise displacement is held by the inherent stiffness of theband itself against edgewise motion, a plurality of abrading elementscarried by the band, means for supporting work to be acted upon by theabrading elements, said means being located in juxtaposition to onestretch of the band as it passes from pulley to pulley sothat the spaceadjacent to the work supporting means constitutes a working zone, abackup support having a longitudinally continuous surface along whichthe band and abrading elementsslide, means rigidly mounting said backupsupport with the ends thereof extending above and beneath the workingzone, said backup support being no wider than the abrading elements, andrigid side walls connected with said backup support at least at one endthereof but outside the working zone, said side walls being sopositioned and spaced apart that the abrading elements slide closelytherebetween whereby the connected band and abrading elements are heldagainst edgewise displacement in juxtaposition to the working zone.

2l. In an abrading machine, the combination of, edgewise spaced pulleys,a flat ribbon-like one-piece metall band encircling the pulleys.' saidband being wide enough to beedgewise inflexible so that a portion oftheband spanning the distance between two supports which .hold the.

same against edgewise displacement is heldv by the inherent stiffness ofthe band'itself against edgewise motion, a plurality of abradingelements carried by the band, means for supporting work to be acted uponby the abrading elements, said means being located in juxtaposition toone stretch of the band as it passes from pulley to pulley so that thespace adjacent to the work supporting means constitutes a working zone,'a backup support having a longitudinally continuous surface along whichthe band and abrading elements slide, means rigidly mounting said backupsupport with the ends thereof extending above and beneath the workingzone, said backup support being no wider than the abrading elements, andspaced walls rigidly connected with the backup support at the endsthereof to be positioned above and beneath the working zone but not inthe working zone, said walls being spaced apart a distance to receivethe abrading elements therebetween and slidably engage the side wallsthereof to thereby support the connected band and abrading elementsagainst edgewise displacement above and beneath the working zone.

22. In a device of the class described, a base, a pair of verticallyspaced pulleys mounted on said base, a metallic exible band trainedabout said pulleys, abrading elements mounted on said band, and meansprojecting from one end of each element interposed between said band andthe adjacent end of the adjacent element when said elements are inlongitudinal alignment so that the latter element laps -over said`projecting means, said lapping portions o! the elements interengagingto prevent relative lateral movement of said elements.

23. In a filing machine, a frame, a pair of vertically spaced pulleyscarried by said frame, a thin atwise flexible metallic band trainedabout said pulleys, le elements secured to said band, a table providinga working zone around one stretch of the band between said pulleysabove, and in proximity to, said table, guides for engaging the. sideedges of said le elements adjacent to but' not in said working zoneforpreventing lateral edgewise movement of said eiements, the edgewisestiffness of said band between said guides preventing lateral edgewisemovement of said band and elements in said working zone, and means forresisting rearward fiatwise movement of said band within said workingzone, said last named means being no wider than said elements.

24. In a ling machine, a frame, a pair of vertically spaced pulleyscarried by said frame, a carrier trained about said pulleys and havingsubstantially straight stretches of travel between the pulleys, leelements mounted on said carrier, the adjacent ends of said elementshaving an overlapping and interlocking connection, said connectioncomprising a projection on one element spaced below the plane of theling surface, said projection having diverging side walls and beingengageable in a complementary recess in the other element whereby thelatter element laps over the projection and a continuous tiling surfaceis provided with the overlapping interlocking connection disposed whollybelow said filing surface, and whereby said connections automaticallyguide the elements into longitudiha. i,

nal alignmentas they leave the pulleys and `begin their straightstretches.

25. In a ming machine, a frame. a pair of vertically spaced pulleyscarried by said frame, a thin exible metallic band trained about saidpulleys, tlie elements secured to said band, a working table secured tosaid frame between said pulleys, guides engaging the side edges of saidnle elements adjacent to, but spaced from, said table, and a backingmember at the level of '.said table for resisting the inward movement ofsaid band and elements during the iling opera'- tion and extending abovethe table to form a working zone, said member at said level being nowider than said elements.

26. In a ling machine, a series of illes of uniform and equal width,interengaglng connections between the ends of the les by which they areheld in longitudinal alignment with their side edges flush, .means forconnecting the les to form an endless ille band, said means beingilexible in adirection ilatwise with respect to theiiles but inexible ina direction edgewise with respect thereto, spaced means mounting anddriving the iile band to cause one stretch thereof to move through aworking zone, Aa worksupport in said working zone for supporting work tobe pressed against the Illing surface of the le band as it passesthrough the working zone, spaced side guides having close slidingengagement with the side edges of the illes to support the ille bandagainst edgewise displacement, means rigidly mounting said side guidesadjacent to but not in the working zone, and a backup support in theworking zone having a continuous longitudinal surface along which thefile band slides to be supported against inward ilatwise motion inresponse to the pressure of work thereon, said backup support being nowider than the illes so as not to interfere with the functioning thereofin corners of work.

27. In a iiling device, a supporting frame, a pair of vertically spacedpulleys supported on said frame, a band trained about said pulleys, atable mounted on said frame in a plane between said pulleys and providedwith an opening through which said band extends, abrading .elements onsaid band, means engaging the side edges of said elements adjacent saidtable for preventing lateral movement of said elements and means at saidtable for preventing rearward movement of said band during the lingoperation, said last named means being no wider than said elements.

LEIGHTONA. WILKIE.

cERTIFIcATE 'oF conREcTIoN. patent No. 2,180,079. e November'lh. 1959-mmHToN A. wILxm.

It is hereby certified that error appears in the `printedslixeoificationA ofthe above numbered patent requiring correction asfollows: Page 6, tiret column, line '52, claim lh, for the word "narrow"read narrower; samp page, second column, line 5h., claim-17, forv "with"readwhioh; 'and that the said Letters Patent shouldbe read with thiscorrection therein that theV same may conform lto the record of the casein the Patent Office.

Signed and sealed this 19th day of December, A; D. 1959.

Henry van Arsdale, (Seal) Acting Comissioner of Patents.

